Design Optimization of a Multi-Stage Axial Compressor Using Throughflow and a Database of Optimal Airfoils

The basic tool set to design multi-stage axial compressors consists of fast codes for throughflow and blade-to-blade anal-ysis. Detailed blade row design is conducted with 3D CFD,mainly to control the end wall flow. This work focuses on the interaction between through-flow and blade-to-blade design and the transition to 3D CFD.A design strategy is presented that is based on a versatile air-foil family. The new class of airfoils is generated by optimizing a large number of airfoil shapes for varying design requirements. Each airfoil geometry satisfies the need for a wide working range as well as low losses. Based on this data, ma-chine learning is applied to estimate optimal airfoil shape and performance. The performance prediction is incorporated into the throughflow code. Based on a throughflow design, the air-foils can be stacked automatically to generate 3D blades. On this basis, a 3D CFD setup can be derived. This strategy is applied to study upgrade options for a15-stage stationary gas turbine compressor test rig. At first, the behaviour of the new airfoils is studied in detail. After-wards, the design is optimized for mass flow rate as well as efficiency. Selected configurations from the Pareto-front are evaluated with 3D CFD